So we almost aced their team and it's 4v1. We go to baron, their one starts coming so 2 peel off to keep him away. Baron has 2k HP. Then for the next 30 seconds baron kept regening which made us lose the game as their whole team came.

Ridiculous bug...

*dunno why the downvotes to clarify, my jungler and I were literally in baron attacking him from the inside constantly and the bastard would regen and not die.